QB Tarvaris Jackson expected to sign with Seahawks

Jackson himself, though, essentially labeled it a done deal in a tweet Wednesday afternoon in response to a question asking if he would soon join the Seahawks: “Headed that way tomorrow to make it official.’’

And one more big clue came in the roster itself. Rookie free-agent safety Ray Polk, who had been wearing the No. 7 that was Jackson’s as a Seahawk, was suddenly wearing No. 38 when the team held its second of three minicamp practices Wednesday.

Still unclear is how the quarterback spot will shake out, assuming Jackson signs.

Seattle, though, also went with just two quarterbacks for much of last season — Russell Wilson and Matt Flynn.

While Seattle coaches have professed confidence in the ability of Quinn to handle the backup job, Jackson would bring an even bigger level of comfort and familiarity with the team and playbook, having started 14 games in the 2011 season.

Receiver Sidney Rice, who played with Jackson in Minnesota as well as the one season with the Seahawks, called the prospect of the return of Jackson “great.’’

Jackson was waived by Buffalo on Tuesday, having spent last year with the Bills after being released by the Seahawks, though he did not see any action in 2012.

“I don’t think he ever wanted to leave (Seattle),’’ Rice said. “It’s a great opportunity for him to be here. He’s got a lot of friends here. Everybody was kind of upset when he left. But we are going to welcome him back with open arms.’’

The Seahawks were 7-7 in the 14 games Jackson started in 2011, finishing 7-9 overall (Charlie Whitehurst started the other two games).

And while his numbers were pedestrian (14 touchdown passes against 13 interceptions and a passer rating of 79.2 — Wilson’s rating was 100.0 in 2012), Jackson earned the respect of teammates for playing through an injury to his pectoral muscle.

“He definitely did (earn the respect of teammates),’’ Rice said. “He’s a tough guy. The things he did for us, playing with that torn pectoral muscle for the whole season, not saying a word, just coming in every day ready to work with the situation he was in, still being in tune to everything, shows a lot of character.’’

Added center Max Unger: “I think this locker room really liked him as a quarterback and we’d love to have him back.’’

Jackson’s mobility — he rushed for 108 yards on 40 carries in 2011 — also would seem to make him a better fit for the direction in which the Seattle offense is moving with Wilson than the more traditional Quinn.

Rice also noted the advantage to have a player with six years of experience and 34 career starts (a record of 17-17 in those games) helping to mentor Wilson.

“I think Russell would take whatever he can get from him,’’ Rice said. “He knows a lot — he played behind Brett Favre for a couple of years (in Minnesota) so it’s great for Russell and (Jackson) to compete with each other and make each other better.’’

Sherman doesn’t take bait

Seahawks cornerback Richard Sherman is known for rarely encountering a topic on which he doesn’t have an opinion. But Sherman decided Wednesday not to wade into a war of words with 49ers coach Jim Harbaugh, who on Tuesday said he had “definitely noticed’’ Seattle’s recent suspensions for performance-enhancing drug use, and that “if you cheat to win, then you’ve already lost.’’

Sherman, asked if he’d seen Harbaugh’s comments, said, “Oh, I don’t worry about him. We keep it here. We keep it in Seattle.’’